Backscatter

Shooting with your strobe too close
to the camera lens causes Backscatter. This lights up tiny particles in the water
and results in our pictures looking like they were shot in a snowstorm!

There are two types of Backscatter...

'Real' Backscatter: particles that are pure white. Usually small
in size and grouped to the pattern of the strobe often with fall off dependant on
distance. It is noticeable even against a light background

'Common' Backscatter: crud in the water that is usually uniform
over the whole image. Usually variable in size and maintaining some color. Is only
really noticeable against a dark background see below.

Backscatter can be rated on a scale of 1-5

Clear - no action required

Hardly noticeable - not worth touching

Noticeable - editing justified

Bad - borderline worth editing

Terminal - not worth editing, bin it!

The above image shows common backscatter and is a 4 on the above scale. Notice how
it is only evident against a darker background. The light foreground suffers from
the same crud yet is not noticeable. Real backscatter is noticeable even against
a light background.